The system of the invention may be incorporated into telephone answering machines of the type including an outgoing message magnetic tape mechanism in which an announcement is recorded on a magnetic tape, and which is activated during an announcement interval in response to ring signals received over the telephone line to cause the recorded announcement to be transmitted over the telephone line to the calling party during that interval; and an incoming message magnetic tape mechanism in which incoming messages are recorded on a magnetic tape in sequence.
The system of the invention may also be incorporated into telephone answering machines in which the outgoing message and incoming messages are recorded on a single tape; and in telephone answering machines in which the outgoing message is recorded in a solid state memory; and in other types of telephone answering machines.
The system of the invention also finds application in telephone answering machines which are equipped with a control system which causes the telephone answering machine to require a relatively large number of ring signals before it will seize the telephone line if no incoming messages have been recorded; but which requires a lesser number of ring signals to seize the line when one or more incoming messages have been received and recorded. Such a control system permits the user to call the machine by long distance from a remote location in order to pick up any messages that might be recorded on the machine. However, if there are no messages, he can then hang up before the machine seizes the telephone line, thus avoiding toll charges.
The system of the invention also finds application in telephone answering machines which are equipped with an indicator lamp that is continuously energized if there are no messages, but which flashes if one or more incoming messages have been received and recorded. This enables the user at a glance to determine whether there are any messages on the machine.
In addition, the system of the invention may be incorporated into telephone answering machines which are equipped with a call counter which indicates to the user how many incoming messages have been received and are recorded on the machine.
Most present-day telephone answering machines are controlled by a microcomputer, and when such telephone answering machines are first energized, the microcomputer goes through a reset routine during which it checks both the outgoing message and incoming message tape mechanisms, and sets both tape mechanisms to their "home" or "origin" positions; and then sets the machine to its "automatic answer" mode ready to respond to the next telephone call. The microcomputer in such machines also automatically sets the ring control system to its multiple ring condition, the call indicator lamp to its continuously energized condition, and the call counter to zero, when the machine is first energized.
In the prior art machines, when the machine is first connected to a power source the internal microcomputer causes both the outgoing message tape and incoming message tape to be set their "home" origin position, the ring control system to be set to its multiple ring state, the call indicator lamp be set to its continous state, and the call counter to be set to zero. However, in the prior art machine the foregoing operations also occur when power is restored after a power failure, and this means that any incoming messages recorded on the incoming message tape prior to the power failure are lost.
The system of the present invention provides a control for a telephone answering machine such that whenever power is applied to the telphone answering machine, the microcomputer first determines if any messages have previously been recorded on the incoming message tape. If such is the case, the incoming message tape is set to a position adjacent to the end of the last incoming message recorded on the tape; the ring control system is set to cause the telephone answering machine to seize the telephone line when the lesser number of rings is received, the call counter is set to a value which casues the indicator lamp to flash indicating that one or more calls have been received.
It is, accordingly, an object of the present invention to provide a relatively simple system in a telephone answering machine which responds, when power is restored after a power failure, to return the machine to the condition it was in just prior to the power failure.